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June 15 2017

15:40

Mapping project will open up new routes to uncharted territory

What if fictional places in books, such as Middlemarch, Treasure Island, Barsetshire and Gormenghast, could be generated as maps and even 3D visualisations out of the text itself?
15:30

US-China collaboration makes excellent start in optimizing lithium to control plasma

For fusion to generate substantial energy, the ultra-hot plasma that fuels fusion reactions must remain stable and kept from cooling. Researchers have recently shown lithium, a soft, silver-white metal, to be effective in both respects during path-setting U.S.-Chinese experiments on the Experimental Advanced Superconducting Tokamak (EAST) in Hefei, China. Leading the U.S. collaboration is the U.S. Department of Energy's (DOE) Princeton Plasma Physics Laboratory (PPPL), together with co-principal investigators Los Alamos and Oak Ridge National Laboratories, with Johns Hopkins University, the University of Illinois at Urbana-Champaign, the University of Tennessee-Knoxville, and the Massachusetts Institute of Technology. Scientists from General Atomics also participate via a separate grant.
15:20

How to educate future therapists more effectively

In the classroom, what's the line between education and personal experience?
15:15

With wireless charging, electric cars could drive forever

Scientists have found a way to wirelessly transmit electricity to a nearby moving object.

The method may have applications in transportation, medical devices, and more. If electric cars could recharge while driving down a highway, for example, it would virtually eliminate concerns about their range and lower their cost, perhaps making electricity the standard fuel for vehicles.

“In addition to advancing the wireless charging of vehicles and personal devices like cellphones, our new technology may untether robotics in manufacturing, which also are on the move,” says Shanhui Fan, a professor of electrical engineering at Stanford University and senior author of the study.

“In theory, one could drive for an unlimited amount of time without having to stop to recharge…”

“We still need to significantly increase the amount of electricity being transferred to charge electric cars, but we may not need to push the distance too much more,” he says.

The group built on existing technology developed in 2007 at MIT for transmitting electricity wirelessly over a distance of a few feet to a stationary object. In the new work, the team transmitted electricity wirelessly to a moving LED lightbulb. That demonstration only involved a 1-milliwatt charge, whereas electric cars often require tens of kilowatts to operate.

The team is now working on greatly increasing the amount of electricity that can be transferred, and tweaking the system to extend the transfer distance and improve efficiency.

Going farther

Wireless charging would address a major drawback of plug-in electric cars—their limited driving range. Tesla Motors expects its upcoming Model 3 to go more than 200 miles on a single charge and the Chevy Bolt, which is already on the market, has an advertised range of 238 miles. But electric vehicle batteries generally take several hours to fully recharge. A charge-as-you-drive system would overcome these limitations.

“In theory, one could drive for an unlimited amount of time without having to stop to recharge,” Fan explains. “The hope is that you’ll be able to charge your electric car while you’re driving down the highway. A coil in the bottom of the vehicle could receive electricity from a series of coils connected to an electric current embedded in the road.”

‘Superlens’ adds range to wireless power transfer

Some transportation experts envision an automated highway system where driverless electric vehicles are wirelessly charged by solar power or other renewable energy sources. The goal would be to reduce accidents and dramatically improve the flow of traffic while lowering greenhouse gas emissions.

Wireless technology could also assist GPS navigation of driverless cars. GPS is accurate up to about 35 feet. For safety, autonomous cars need to be in the center of the lane where the transmitter coils would be embedded, providing very precise positioning for GPS satellites.

Made with magnets

Mid-range wireless power transfer is based on magnetic resonance coupling. Just as major power plants generate alternating currents by rotating coils of wire between magnets, electricity moving through wires creates an oscillating magnetic field.

This field also causes electrons in a nearby coil of wires to oscillate, thereby transferring power wirelessly. The transfer efficiency is further enhanced if both coils are tuned to the same magnetic resonance frequency and are positioned at the correct angle.

However, the continuous flow of electricity can only be maintained if some aspects of the circuits, such as the frequency, are manually tuned as the object moves. So, either the energy transmitting coil and receiver coil must remain nearly stationary, or the device must be tuned automatically and continuously—a significantly complex process.

To address the challenge, the research team eliminated the radio-frequency source in the transmitter and replaced it with a commercially available voltage amplifier and feedback resistor. This system automatically figures out the right frequency for different distances without the need for human interference.

“Adding the amplifier allows power to be very efficiently transferred across most of the three-foot range and despite the changing orientation of the receiving coil,” says graduate student Sid Assawaworrarit, the study’s lead author. “This eliminates the need for automatic and continuous tuning of any aspect of the circuits.”

Assawaworrarit tested the approach by placing an LED bulb on the receiving coil. In a conventional setup without active tuning, LED brightness would diminish with distance.

In the new setup, the brightness remained constant as the receiver moved away from the source by a distance of about three feet. Fan’s team recently filed a patent application for the latest advance.

Panel would turn room into wireless charging station

The group used an off-the-shelf, general-purpose amplifier with a relatively low efficiency of about 10 percent. They say custom-made amplifiers can improve that efficiency to more than 90 percent.

“We can rethink how to deliver electricity not only to our cars, but to smaller devices on or in our bodies,” Fan says. “For anything that could benefit from dynamic, wireless charging, this is potentially very important.”

The TomKat Center for Sustainable Energy at Stanford supported part of the work.

Source: Stanford University

The post With wireless charging, electric cars could drive forever appeared first on Futurity.

15:14

'Magic' alloy could spur next generation of solar cells

In what could be a major step forward for a new generation of solar cells called "concentrator photovoltaics," University of Michigan researchers have developed a new semiconductor alloy that can capture the near-infrared light located on the leading edge of the visible light spectrum.
15:12

Jerusalem tower younger than thought

Gihon Spring, just downhill from the ancient city of Jerusalem, was crucial to the survival of its inhabitants, and archaeologists had uncovered the remains of a massive stone tower built to guard this vital water supply. Based on pottery and other regional findings, the archaeologists had originally assigned it a date of 1,700 BCE. But new research conducted at the Weizmann Institute of Science provides conclusive evidence that the stones at the base of the tower were laid nearly 1,000 years later. Among other things, the new results highlight the contribution of advanced scientific dating methods to understanding the history of the region.
15:00

Smart materials used in ultrasound behave similar to water, chemists report

A team of researchers at the University of Pennsylvania is gaining new insight into the smart materials used in ultrasound technology. While forming the most thorough model to date of how these materials work, they have found striking similarities with the behavior of water.
14:51

Our sun likely had a twin called ‘Nemesis’

When our sun was born 4.5 billion years ago, it was almost certainly part of pair—but that’s true of every other sun-like star in the universe.

Many stars have companions, including our nearest neighbor, Alpha Centauri, a triplet system. Astronomers have long sought an explanation. Are binary and triplet star systems born that way? Did one star capture another? Do binary stars sometimes split up and become single stars?

Astronomers have even searched for a companion to our sun, a star dubbed Nemesis because it was supposed to have kicked an asteroid into Earth’s orbit that collided with our planet and exterminated the dinosaurs. But, it’s never been found.

The new theory is based on a radio survey of a giant molecular cloud filled with recently formed stars in the constellation Perseus, and a mathematical model that can explain the Perseus observations only if all sun-like stars are born with a companion.

“We are saying, yes, there probably was a Nemesis, a long time ago,” says coauthor Steven Stahler, a research astronomer at the University of California, Berkeley.

“We ran a series of statistical models to see if we could account for the relative populations of young single stars and binaries of all separations in the Perseus molecular cloud, and the only model that could reproduce the data was one in which all stars form initially as wide binaries. These systems then either shrink or break apart within a million years.”

Telescopes spot galaxy bursting with new stars

In the new study, which has been accepted by the Monthly Notices of the Royal Astronomical Society, “wide” means that the two stars are separated by more than 500 astronomical units, or AU, where one astronomical unit is the average distance between the sun and Earth (93 million miles). A wide binary companion to our sun would have been 17 times farther from the sun than its most distant planet today, Neptune.

Based on this model, the sun’s sibling most likely escaped and mixed with all the other stars in our region of the Milky Way galaxy, never to be seen again.

“The idea that many stars form with a companion has been suggested before, but the question is: how many?” says first author Sarah Sadavoy, a NASA Hubble fellow at the Smithsonian Astrophysical Observatory. “Based on our simple model, we say that nearly all stars form with a companion. The Perseus cloud is generally considered a typical low-mass star-forming region, but our model needs to be checked in other clouds.”

Litter of stars

The idea that all stars are born in a litter has implications beyond star formation, including the very origins of galaxies, Stahler says.

Astronomers have speculated about the origins of binary and multiple star systems for hundreds of years, and in recent years have created computer simulations of collapsing masses of gas to understand how they condense under gravity into stars. They have also simulated the interaction of many young stars recently freed from their gas clouds. Several years ago, one such computer simulation by Pavel Kroupa of the University of Bonn led him to conclude that all stars are born as binaries.

Yet direct evidence from observations has been scarce. As astronomers look at younger and younger stars, they find a greater proportion of binaries, but why is still a mystery.

“The key here is that no one looked before in a systematic way at the relation of real young stars to the clouds that spawn them,” Stahler says. “Our work is a step forward in understanding both how binaries form and also the role that binaries play in early stellar evolution. We now believe that most stars, which are quite similar to our own sun, form as binaries. I think we have the strongest evidence to date for such an assertion.”

Did quasars stop galaxies from making tons of stars?

Astronomers have known for several decades that stars are born inside egg-shaped cocoons called dense cores, which are sprinkled throughout immense clouds of cold, molecular hydrogen that are the nurseries for young stars. Through an optical telescope, these clouds look like holes in the starry sky, because the dust accompanying the gas blocks light from both the stars forming inside and the stars behind. The clouds can, however, be probed by radio telescopes, since the cold dust grains in them emit at these radio wavelengths, and radio waves are not blocked by the dust.

The Perseus molecular cloud is one such stellar nursery, about 600 light-years from Earth and about 50 light-years long. Last year, a team of astronomers completed a survey that used the Very Large Array, a collection of radio dishes in New Mexico, to look at star formation inside the cloud. Called VANDAM, it was the first complete survey of all young stars in a molecular cloud, that is, stars less than about 4 million years old, including both single and multiple stars down to separations of about 15 astronomical units. This captured all multiple stars with a separation of more than about the radius of Uranus’ orbit—19 AU—in our solar system.

Stahler heard about the survey after approaching Sadavoy, a member of the VANDAM team, and asking for her help in observing young stars inside dense cores. The VANDAM survey produced a census of all Class 0 stars—those less than about 500,000 years old—and Class I stars—those between about 500,000 and 1 million years old. Both types of stars are so young that they are not yet burning hydrogen to produce energy.

Sadavoy took the results from VANDAM and combined them with additional observations that reveal the egg-shaped cocoons around the young stars. These additional observations come from the Gould Belt Survey with SCUBA-2 on the James Clerk Maxwell Telescope in Hawaii. By combining these two data sets, Sadavoy was able to produce a robust census of the binary and single-star populations in Perseus, turning up 55 young stars in 24 multiple-star systems, all but five of them binary, and 45 single-star systems.

Using these data, Sadavoy and Stahler discovered that all of the widely separated binary systems—those with stars separated by more than 500 AU—were very young systems, containing two Class 0 stars. These systems also tended to be aligned with the long axis of the egg-shaped dense core. The slightly older Class I binary stars were closer together, many separated by about 200 AU, and showed no tendency to align along the egg’s axis.

‘It isn’t random’

“This has not been seen before or tested, and is super interesting,” Sadavoy says. “We don’t yet know quite what it means, but it isn’t random and must say something about the way wide binaries form.”

The researchers mathematically modeled various scenarios to explain this distribution of stars, assuming typical formation, breakup, and orbital shrinking times and concluded that the only way to explain the observations is to assume that all stars of masses around that of the sun start off as wide Class 0 binaries in egg-shaped dense cores, after which some 60 percent split up over time. The rest shrink to form tight binaries.

“As the egg contracts, the densest part of the egg will be toward the middle, and that forms two concentrations of density along the middle axis. These centers of higher density at some point collapse in on themselves because of their self-gravity to form Class 0 stars.”

“Within our picture, single low-mass, sun-like stars are not primordial,” Stahler says. “They are the result of the breakup of binaries.”

Their theory implies that each dense core, which typically comprises a few solar masses, converts twice as much material into stars as was previously thought.

Stahler has been asking radio astronomers to compare dense cores with their embedded young stars for more than 20 years, in order to test theories of binary star formation. The new data and model are a start, but more work needs to be done to understand the physics behind the rule.

Such studies may come along soon, Sadavoy says, because the capabilities of a now-upgraded VLA and the ALMA telescope in Chile, plus the SCUBA-2 survey in Hawaii, “are finally giving us the data and statistics we need. This is going to change our understanding of dense cores and the embedded stars within them.”

Source: UC Berkeley

The post Our sun likely had a twin called ‘Nemesis’ appeared first on Futurity.

14:50

Taking circular economy to the next level

In recent years a growing number of businesses, governments and environmental advocates have embraced the concept of a "circular economy," which aims to achieve greater sustainability by keeping more resources and materials in use for as long as possible—through strategies such increased product durability, reuse and recycling.
14:43

An alternative hypothesis on the faunal colonization of the Himalayas?

Until now, the fauna of the Himalayas was considered to be an "immigration fauna", with species that have immigrated primarily from neighbouring regions to the west and east since the geological formation of this mountain range. Using molecular-genetic methods, a German-Chinese research team has now tested an alternative colonization hypothesis on lazy toads (Pelobatoidea). The findings indicate that this group arose earlier than assumed in southern Tibet, and went on to colonize the Himalayas from there after its formation. The immigration and evolution of many species in the Himalayas might therefore have taken a different course than previously assumed.
14:43

First few millimeters of the leaf margin identify palm species in a new key to Syagrus

An incredible amount of information is contained in the very first few millimeters of the leaflet margin of species in the Neotropical palm genus Syagrus.
14:41

Researchers discover shortcut to satellite-based quantum encryption network

In a new study, researchers demonstrate ground-based measurements of quantum states sent by a laser aboard a satellite 38,000 kilometers above Earth. This is the first time that quantum states have been measured so carefully from so far away.
14:40

Radio astronomers peer deep into the stellar nursery of the Orion Nebula

Astronomers have released an image of a vast filament of star-forming gas, 1200 light-years away, in the stellar nursery of the Orion Nebula.
14:33

Nazi police files suggest some tolerance for lesbians

The Nazi regime in Germany may have been more tolerant of lesbians than might be expected, new research suggests.

Discoveries from police investigation files from the 1940s involving alleged violations of same-sex relations laws and their analysis appear in the Journal of Contemporary History.

“These files add a new level of nuance to existing scholarship,” says study author Samuel Clowes Huneke, a doctoral candidate in history at Stanford University. “They hint at a more normal existence that was the daily experience of some lesbians in the Third Reich.”

The work sheds light on “the complex negotiation of both repression and toleration on which authoritarian regimes depend,” says Huneke.

“…the regime’s seeming lack of interest in female homosexuality is startling.”

Records have well-documented the systematic persecution of gay men under the Nazi regime. The regime’s laws explicitly criminalized homosexual acts between men. About 50,000 men were convicted for being homosexuals and between 5,000 and 15,000 were imprisoned in concentration camps, where up to 60 percent of them died, according to scholars.

But how lesbians fared is less clear. Females were excluded from the law that made homosexual acts illegal. Aside from a few cases that have been uncovered by a handful of scholars in the United States and Germany, little documentation exists describing how the Nazis treated lesbians.

This lack of evidence has led historians to debate whether lesbians had it easier than gay men during the Nazi period. Some scholars argue that the Nazi government did not persecute lesbians to the same degree because women in general were not seen as sexual beings or as threatening to the regime’s policy of pronatalism, which encouraged reproduction.

PR puff pieces made Hitler seem likable

Huneke, while agreeing with those views, also argues that Nazi officials believed lesbians posed less of a political threat to the regime because women were barred from most spheres of politics and public life.

“In light of both the fearsome persecution of homosexual men and scholarship that places it in the context of National Socialist pronatalism, the regime’s seeming lack of interest in female homosexuality is startling, for in other respects the government placed considerable burdens on women,” writes Huneke, who is working on a dissertation about the history of homosexuality in postwar Germany.

Four cases from the archives

The German criminal police, also known as the Kriminalpolizei, or Kripo, investigated eight women as part of four separate cases that Huneke examined.

The files, which Huneke discovered in 2015 at the Landesarchiv Berlin, or Berlin state archive, included signed statements from witnesses and the accused women.

In each case, someone the woman knew—a neighbor, coworker, or parent—denounced her for allegedly violating the laws against same-sex relations.

“That these eight women were denounced to the Berlin criminal police in the early 1940s is striking on its own, given the archival silence when it comes to female homosexuality,” Huneke writes.

In each case, the police, a judge, or a state’s attorney determined that the women could not be prosecuted for same-sex relations under the criminal code. There is no evidence that any of the eight women investigated were punished as a result of the denunciations, Huneke says.

Poetry of the Holocaust gets new translation

“To scholars accustomed to seeing in the Nazi state a jungle of overlapping jurisdictions, personal initiative, and law based solely on the Führer’s wish, this is a curious portrait of the Nazi justice system, one marked by an unexpected concern for the strict interpretation of statute,” Huneke writes.

‘Frankly bizarre’

The case of Margot Liu née Holzmann, whose lesbian relationship was also documented in a recent German monograph, struck Huneke as particularly strange.

“But simply because there was a tolerance for female homosexuality doesn’t mean that these women led enviable lives.”

Holzmann was a Jewish lesbian who lived in Nazi Berlin. In 1941, she married a Chinese waiter and received Chinese citizenship, which the police insisted shielded her from deportation to a concentration camp. Once Holzmann’s husband became aware of her lesbian relationship, he filed for divorce and contacted the police.

Yet, as in the other three cases, the police opted not to intervene. “It is frankly bizarre that the criminal police would insist, in multiple documents, on the protections conferred a German Jewish lesbian by virtue of her de jure Chinese citizenship,” Huneke writes.

Huneke emphasizes that his analysis is limited in scope. For example, the same detective was responsible for the findings in all four cases, and Huneke says that particular officer could have just been less zealous than other officers.

“But the fact that they were so persnickety in following every detail of the law in these cases—it suggests a level of toleration,” Huneke says.

Apathy? Tolerance?

In addition to each woman eluding punishment, the files showed that many of them led fairly open lesbian lives, sometimes for years, before finally being denounced to the police. “The files ironically show that there was a significant ability on the part of ordinary Germans to witness lesbianism and not go ahead and denounce the person,” Huneke says.

But Huneke adds that this apathy toward lesbianism may have come about because of the Nazi regime’s non-threatening view of women.

“Gender is perhaps why lesbians weren’t persecuted in the same ways,” Huneke says. “But simply because there was a tolerance for female homosexuality doesn’t mean that these women led enviable lives.” In his article, he writes that “these files throw into sharper relief the duplicity of tolerance that has characterized societies’ views of female sexuality for centuries.”

Huneke says his work demonstrates that dictatorships often rely not only on overt oppression but also on limited tolerance of certain groups.

“It is a divide-and-conquer approach,” Huneke says. “One of the most important takeaways from this research, to my mind, is to break the popular idea that authoritarian governments maintain their power only through repression.”

Source: Stanford University

The post Nazi police files suggest some tolerance for lesbians appeared first on Futurity.

14:30

US is still first in science, but China rose fast as funding stalled here & elsewhere

American scientific teams still publish significantly more biomedical research discoveries than teams from any other country, a new study shows, and the U.S. still leads the world in research and development expenditures.
14:20

From bleeps of 'Pong' and 'Mario,' game music comes of age

The electronic bleeps and squawks of "Tetris," ''Donkey Kong" and other generation-shaping games that you may never have thought of as musical are increasingly likely to be playing at a philharmonic concert hall near you.
14:16

Crystal DDT could be a safer bug-killer

Scientists have found a new crystal form of the pesticide DDT that is more effective against insects than the current form.

Their research, which appears in the journal Angewandte Chemie, points to the possibility of developing a new version of solid DDT that can be administered in smaller amounts while reducing environmental impact.

The pesticide has historically been linked to human-health afflictions and environmental degradation.

“Make no mistake: DDT in its known state has been proven time and again to be damaging to our environment, most notably wildlife,” says Bart Kahr, a New York University chemistry professor and the paper’s senior author.

“However, our discovery of a new DDT crystal, which we’ve shown to be more successful and in smaller amounts in eradicating harmful insects, suggests that the creation of a safer pesticide is within reach,” adds Kahr.

“The finding is a surprising one as, for decades, DDT crystals were thought to exist in only one form,” adds coauthor Michael Ward, also a chemistry professor. “This new knowledge opens the door to future development of a more effective product that could diminish the dangers posed by existing forms.”

In a related and accompanying essay in Angewandte Chemie, Kahr, Ward, and Jingxiang Yang, one of the study’s coauthors, describe attempts by the chemical industry and others to diminish the dangers of DDT as an insecticide by misrepresenting scientific data and by attacking the legacy of biologist Rachel Carson. Carson’s 1962 work Silent Spring uncovered the environmental damage caused by DDT and other pesticides.

In the essay, Kahr, Ward, and Yang report their analysis of primary toxicology data, positing that DDT advocates not only mischaracterize the findings of Carson and others, but use a false DDT narrative to oppose any and all environmental regulation.

The Environmental Protection Agency banned DDT in the United States in 1972; it was later banned or restricted in other nations under the Stockholm Convention on Persistent Organic Pollutants. However, it may still be used in certain health emergencies—its effectiveness against mosquitoes has aided in stemming the spread of malaria, although over time mosquitos have become resistant to DDT, which is to be expected for rapidly reproducing species.

Wandering pesticides end up in ‘beebread’

DDT was first synthesized in the 19th century but its action against insects was only discovered in 1939. After DDT solutions are sprayed, crystals emerge from deposited solutions. Insects then must walk upon crystals of DDT molecules and absorb the poison through their hydrophobic footpads.

In general, chemical compounds can crystallize as different forms that are distinguished by the arrangement of their atoms, ions, or molecules. However, DDT crystals were long thought to exist in only one form.

The scientists identified the new form by watching crystals grow. Then they tested the efficacy of both the long-known DDT crystal (Form I) and the newly uncovered one (Form II) against fruit flies. Here they not only found that Form II was superior to Form I against these insects, but also that the new crystal could be more effective in smaller amounts.

“The possibility that one crystalline form may be more active than another provides an opportunity to optimize pesticide formulations with a reduced amount of compound applied, achieving the necessary protection, whether against disease or infestation, while minimizing environmental impact,” observes Ward.

Kids exposed to pesticides have smaller lungs

Additional study authors are from NYU and the University of Nevada, Las Vegas. The National Science Foundation, NSF’s Materials Research Science and Engineering Center (MRSEC) program, the National Nuclear Security Administration under the Stewardship Science Academic Alliances program through a Department of Energy Cooperative Agreement, and the China Scholarship Council supported the study.

Source: New York University

The post Crystal DDT could be a safer bug-killer appeared first on Futurity.

14:10

One million sign petition for EU weedkiller ban

More than one million people have signed a petition demanding the EU ban the Monsanto weedkiller glyphosate over fears it causes cancer, campaigners said Thursday.
14:00

Swimming robot to probe damage at Japan nuclear plant

A Japanese industrial group unveiled Thursday a swimming robot designed for underwater probes of damage from meltdowns at the Fukushima Dai-Ichi nuclear plant after the March 2011 earthquake and tsunami.
13:50

Water management interventions push scarcity downstream

Large-scale interventions to water resources, such as irrigation, dams and reservoirs, and water withdrawals, have been essential to human development. But interventions tend to solve water scarcity problems at a local level, while aggravating water scarcity downstream.
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